Flow Regime Transition in Open-Cell Solid Foam Packed Reactors: Adaption of the Relative Permeability Concept and Experimental Validation

Abstract

The trickle-to-pulse flow regime transition in silicon-infiltrated silicon carbide (SiSiC) foam packed fixed bed reactors has been investigated. Based on the film stability concepts of Grosser et al. [AIChE J. 1988, 34, 1850. DOI: 10.1002/aic.690341111] as well as Attou and Ferschneider [Chem. Eng. Sci. 2000, 55, 491. DOI: 10.1016/S0009-2509(99)00344-9], two predictive models have been adapted to foams’ specific geometric parameters. To account for the different nature of solid foams and their interactions with various fluids, the fixed bed characteristics (specific surface area and bed porosity) and fluid specific parameters (gas and liquid density, liquid viscosity, surface tension) have been incorporated in the model. Ergun parameters and static liquid holdup which are required for the modeling of the prevailing tractive forces were determined experimentally. The modeling results were compared to regime transition measurements performed for SiSiC solid foams with different linear pore densities (20, 30...